1. Field of the Invention
The present invention relates to a shutter curtain for a building opening, such as a window or door, fitted to a building such as a house or an office building.
2. Description of Related Art
A shutter curtain for a building opening is usually wound to, for example, a take-up drum and it is raised/lowered while being guided by guide rails formed on the two vertical end portions of an opening of the building. The shutter curtain must be constituted in such a manner that it can be curved so as to be wound to the take-up drum from an attitude of a straight line along the guide rails. Accordingly, a conventional shutter curtain is constituted by interlocked slats each of which is formed by bending an elongated plate, so that it can be curved. However, a problem arises in the conventional shutter curtain in that noise cannot be eliminated when the shutter curtain is raised/lowered or it receives wind when it is lowered because the interlocked portions involve a gap which will result in looseness.
Accordingly, although an attempt has been made to eliminate the gaps in the interlocked portions, another problem arises in that the structure of the interlocked portion becomes too complicated to be used practically.